login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A129451 as a simple table

na(n)
01
1-2
22
3-2
41
5-2
62
7-2
83
90
102
11-2
122
13-2
140
15-4
162
17-2
182
190
201
21-2
224
23-2
240
25-2
262
27-2
283
29-2
302
310
322
33-2
340
35-2
364
37-2
382
390
402
41-4
420
43-4
440
45-2
462
47-2
481
490
504
51-2
522
530
542
55-2
562
57-4
582
590
603
61-2
622
63-2
640
650
662
67-4
682
690
702
71-4
722
73-2
740
750
762

[1,-2,2,-2,1,-2,2,-2,3,0,2,-2,2,-2,0,-4,2,-2,2,0,
 1,-2,4,-2,0,-2,2,-2,3,-2,2,0,2,-2,0,-2,4,-2,2,0,2,
 -4,0,-4,0,-2,2,-2,1,0,4,-2,2,0,2,-2,2,-4,2,0,3,-2,
 2,-2,0,0,2,-4,2,0,2,-4,2,-2,0,0,2]